Homeostasis

1. 2014 OKPIK Cold Weather Leader Training Homeostasis

2. Homeostasis The ability or tendency of an organism or a cell to maintain internal equilibrium by adjusting its physiological processes. The processes used to maintain such bodily equilibrium.

3. Why do we care? To function properly, your body must maintain an even temperature (98.6°F or 37ºC) around vital organs within your torso. A few degrees too high or too low can allow serious illness and, if unchecked, death.

4. How we lose heat Radiation Conduction Convection Evaporation Respiration

5. How we lose heat

6. Radiation Is a leading cause of heat loss in almost any situation. The head is the most efficient part of the body’s radiator system. An unprotected head can lose up to ½ the body’s total heat production at 40ºF, and up to ¾ of total body heat production at 5ºF. When your feet are cold put on a hat!

7. Conduction Ordinarily, only small amounts of body heat are lost by conduction. But winter campers tend to lose more heat this way due to the fact that they carry metal tools and sit on frozen rocks or snow banks. Handling gasoline or other liquid fuels at low temperatures is especially dangerous. Spilling this liquid on your hands can cause instant frostbite.

8. Convection Is an active avenue of body heat escape in the outdoors. By radiation, the body continuously warms a thin layer of air next to the skin to a temperature nearly equal to that of the skin. If this warm layer of air is being constantly removed by a brisk wind, you feel cool and have to put on more clothing.

9. Evaporation The evaporation of sweat from the skin and the insensible evaporation of water from the skin and lungs account for a substantial loss of body heat. There is little you can due to prevent this loss. In fact, you should wear clothing that breathes, if the vapor cannot pass through your clothing it will condense and freeze.

10. Respiration Inhaling cool air and exhaling warm air accounts for a significant amount of heat loss. There is little you can do to prevent this.

11. Upper body heat loss

12. Prevent heat loss Keep the body core warm. Keep activity rate and clothing appropriate for the weather conditions. Keep blood circulating freely, avoid tight fitting clothing. Select the proper type and amount of clothing. Don’t wait until you are cold to put on more clothing.

13. How to add heat The most basic way is to eat, the body needs fuel to keep warm. Don’t forget to Drink, your body needs water to digest food.

14. Keep COLD to stay warm keep Clean avoid Overheating wear Layers stay Dry Remember this key; it will help you learn techniques for staying warm while camping in cold weather.

15. Proper Layering Wicking Warm Wind